Algaecide composition having improved stability

ABSTRACT

An algaecide composition having improved stability comprising an aqueous solution containing a complex which is a reaction product of either a copper salt or a cobalt salt with an alkanolamine. The solution also contains an effective amount of an acetylenic diol and an alkali metal halogenate, such as sodium chlorate, which aid in preventing the complex from decomposing during extended periods of storage.

United States Patent 91 Kunkel et al.

[ Feb. 13, 1973 I ALGAECIDE COMPOSITION HAVING IMPROVED STABILITY [76]Inventors: Donald H. Kunkel, Route No. 2 Box 9, Eagle; Donald E.Seymour, 2608.

East Newton Avenue, Milwaukee, both of Wis.

22 Filed: April 28, 1970 211 App]. No.: 32,780

[52] US. Cl ..71/67, 7l/DlG. l [51] Int. Cl.....' ..AOIn 11/04 [58]Field of Search ..71/67, 122

[56] References Cited UNlTED STATES PATENTS 2/1956 Domogalla.........71/67 OTHER PUBLICATIONS Voine Sev et a1. Chem. Abst. Vol. 67 (1967)90004g.

Primary ExaminerLewis Gotts Assistant ExaminerCatherine L. MillsAttorney-Andrus, Sceales, Starke & Sawall [57] ABSTRACT An algaecidecomposition having improved stability 8 Claims, No Drawings ALGAECIDECOMPOSITION HAVING IMPROVED STABILITY This invention relates to analgaecide composition and more particularly to an algaecide compositionhaving improved stability.

Rivers, lakes, streams, drinking water supplies, irrigation systems,agricultural water systems, aquariums, fountains or ornamental watersystems, fish ponds, swimming pools, shower rooms, and industrial watersystems are frequently polluted by the excessive growth of algae andother. microorganisms which impart a distasteful appearance and odor tothe water,

generally interfere with the flow of the water, and may be harmful tohealth. In the past a complex formed by the reaction of a copper saltand alkanolamine, as disclosed in United States Pat. No. 2,734,028, hasbeen used and has achieved a wide success as an algaecide to destroy andcontrol the growth of algae. Acomplex of this type has the ability tomaintain the copper ions in solution and prevent formation of insolublecopper carbonates and hydroxides even in waters containing highproportions of carbonates, bicarbonates, or other dissolved solids.

A copper complex of this type is normally packaged in a concentratedform in glass, plastic or metal containers and is apt to be stored forextended periods. It has been found that when this complex is storedover long periods of time, and particularly when the containers may besubject to sunlight, decomposition of the complex may occur, resultingin a precipitation .of the copper. Precipitation of the copper removesthe toxic copper ions from solution and thus decreases the effectivenessof the complex when diluted and added to the water to be treated. Inaddition, precipitated copper can cause turbidity or cloudiness in thetreated water, and as excessive amounts of copper settle out it can forma sludge or deposit, which is the case of a lake of stream, may tend todestroy the fish life or zooplankton which is essential as fish food. I

The present invention is directed to an algaecide composition containinga copper or cobalt complex and having unexpected and improvedeffectiveness against algae and certain varieties of aquatic weeds, aswell as having improved stability so that the complex will not decomposeover extended periods of storage. The algaecide composition is anaqueous solution containing a complex formed by the reaction of either acopper or cobalt salt and an alkanolamine. The improved stabilityis'brought about by the addition of an effective amount of an acetylenicdiol and alkali metal halogenate.

The salt employed to form the complex can be any water soluble salt ofcopper or cobalt, such as the sulfate, chloride, bromide, acetate,nitrate, citrate, or the like.

The alkanolamine includes at least one alkanol group containing from oneto 10 carbon atoms and may consist of monoethanolamine, diethanolamine,triethanolamine, dimethyl-ethanolamine, diethylethanolamine,aminoethylethanolamine, monoisopropanolamine, diisopropanolamine,triisopropanolamine, methyldiethandlamine, and the like. Of the abovenamed compounds triethanolamine has been found to be a very economicaland effective agent for use with water soluble copper salts because itrequires a smaller amount of the triethanolamine than the other aminesto keep the copper ions in solution, while mono-ethanolamine has beenmost effective with the cobalt salts. To form the complex, thealkanolamine is generally used in a weight ratio of 1 to 2 parts to onepart of the copper or cobalt salt. The resulting complex ion willmaintain the metal in solution in a variety of hard waters containingsubstantial concentrations of alkaline earth metal carbonates andbicarbonates. In addition, the salts or esters of the abovealkanolamines can be employed with equal results. It is believed thatthe hydroxy groups aid in bringing about the formation of the solublecopper or cobalt complex.

The acetylenic diol has the following chemical structure:

HOCH (-C E C), CH OH where n is an integer of 1 m2. Specific examples ofacetylenic diols to be used are 2-butyne-l,4 diol (HOCH C C-C H OH) and2,4,hexadiene-1,6 diol (HOCH C C-C E C CH OH). Esters of the acetylenicdiols can also be used.

The acetylenic diol or its esters is used in a weight ratio of 0.00121to 10:1 with respect to the complex, based on 100 percent activeingredients, and preferably in the weight ratio of 0. l :1 to 1:1.

The alkali metal halogenate, such as sodium or potassium chlorate orbromate, is employed in the weight ratio of 0.001 :1 to 10:1 withrespect to the complex, based on 100 percent active ingredients, andpreferably in the weight ratio of 0. 1 :1 to 1:1.

The precise mechanism by which the acetylenic diol and alkali metalhalogenate aid in increasing the stability of the complex is notcompletely understood, but the combination of these compounds preventsthe breakdown of the complex and the resulting precipitation of copperor cobalt salts on the bottom and sides of the container.

It has also been found that the pH of the aqueous solution has an effecton the stability of the complex. The pH of the solution should be in therange of 5.0 to 12.0 and preferably in the range of 7.4 to 8.0 whenusing the copper complex, and in the range of 9.5 to 10.5 when dealingwith the cobalt complex. 1f the pH is between 6.8 and 7.4 the complexwill tend to decompose more rapidly. Thus,'if the pH of the coppercomplex solution is in the range of 7.4 to 8.0 after mixing of thevarious constituents, the pH can be adjusted upwardly to the desiredvalue by the addition of sodium hydroxide or any other conventionalalkaline material, or can be adjusted downwardly by the addition of anacidic material.

The algaecide composition is generally packaged in concentrated formcontaining at least 50 percent, and preferably 50 to percent by weightof the complex. This high concentration of solids not only aids inpreventing decomposition of the complex but also provides economies inshipping and handling. At the location of use the algaecide compositionis diluted in a ratio of 5 parts to 200 parts of water for each part ofthe concentrated algaecide composition. The dilute solution is thenapplied to the body of water such that the The use of the acetylenicdiol and the alkali metal halogenate acts to prevent decomposition ofthe com-.

plex, so that the algaecide composition can be stored for extendedperiods in transparent containers.

By maintaining the copper or cobalt ions in solution over extendedperiods of storage a more effective use of the toxic metal ions I isachieved and unesirable precipitation or deposits of the metal ions areminimized.

The algaecidal composition is effective against all common forms ofalgae, including filamentous algae, such as Cladaphora and Spirogyra,planktonic algae such as Anacystis and Anaebena, chara algae such asChara vulgaris and Nitella and swimming pool -Algae such as black, brownand red algae. It has been found that the composition of the inventioncontaining the acetylenic diol and the alkali metal halogenate hasincreased algaecidal effectiveness as compared to like concentrations ofthe complex alone.

In addition to its algaecidal effect, the composition, due to theaddition of the acetylenic diol and the alkali metal halogenate, alsotends to function as a defoliant or herbicide, depending on theconcentration of the ac tive ingredients, and has unexpectedeffectiveness against certain higher aquatic plants such as Hydrilla andSouthern Niad.

With the use of the composition of the invention, the copper complex ismore readily absorbed by the algae and aquatic weeds than other coppercompounds used in prior art algaecides, with the result that thecomposition has increased effectiveness. In addition, the composition isextremely persistent in that the absorbed copper complex appears to bereturned to the body of water after destruction of the algae or aquaticweeds so that an effective concentration of the complex is maintained inthe water for extended periods.

As a further advantage, the composition of the invention has been foundto have a beneficial effect on certain types of fish diseases, such asfin rot, Saprolegnia (white fungus), gill disease and whirling disease.

The following examples illustrate the preparation and use of thealgeacide composition of the invention.

EXAMPLE NO. 1

700 gallons of a copper sulfate-triethanolamine complex were prepared bymixing 2,100 pounds of copper sulfate with 315 gallons of 85 percentcommercial grade triethanolamine and 250 gallons of water. The resultingaqueous solution contained 72 percent by weight of the complex and thepH of the solution was adjusted to 7.5 by the addition of sodiumhydroxide solution. One quart of a 35 percent aqueous solution of2-butyne-1,4-diol and 2.09 pounds of sodium chlorate were added to 50gallons of the copper complex solution and samples of this mixturewere'stored in transparent plastic containers. After a period of 12weeks at room temperature, there was no visible deposit or precipitationin the containers and the solutions remained clear.

Control samples containing the same concentration of coppersulfate-triethanolamine complex, but without the addition of theacetylenic diol and sodium chlorate, were similarly stored at roomtemperature and after a 12 hour period a precipitate had formed on boththe side walls and bottoms of all containers containing the controlsamples.

EXAMPLE NO. 11

3 pounds of cobalt chloride and 2.2 pounds of monoethanolamine wereadded to 4.75 pounds of water. The resulting solution had a pH of 9.5and it was adjusted to 10.0 by the addition of aqueous sodium hydroxide.

To 1 gallon of this cobalt complex solution were added 19 c.c. of a 35percent aqueous solution of 2-butyne-1,4-diol and 19 gr. of sodiumchlorate. Samples of the mixture were stored in transparent plasticcontainers. After a period of 12 weeks at room temperature, there was novisible deposit or precipitation in'the containers and the solutionsremained clear.

Control samples containing the same concentration of the cobalt complex,but without the addition of the acetylenic diol and sodium chlorate,were similarly stored at room' temperature and after a 12 hour period aprecipitate had formed on both the side walls and bottoms of allcontainers containing the control samples.

Various modes of carrying out the invention are contemplated as beingwithin the scope of the following claims particularly pointing out anddistinctly claiming the subject matter which is regarded as theinvention.

We claim:

1. An algaecide composition having improved stability, consistingessentially of an aqueous solution containing an effective amount of acomplex produced by reacting a water soluble metal salt selected fromthe group of copper salts and cobalt salts with an alkanolamine havingat least one alkanol group containing from one to ten carbon atoms, saidsolution also having dissolved therein an acetylenic diol and an alkalimetal halogenate to provide increased stability for the complex andprevent decomposition of the same and precipitation of metal salts, saidacetylenic diol having the following structure:

Ho CH (C C )n CH Ol-l where n is an integer of l or 2, saidacetylenicdiol being present in a weight concentration of 0.00121 to10:1 with respect to the complex, and said alkali metal halogenate beingpresent in a weight concentration of 0.00l:1 to 10:1 with respect to thecomplex.

2. The composition of claim 1, wherein said acetylenic diol is2-butyne-l ,4 diol.

3. The composition of claim 1, wherein said alkali metal halogenate issodium chlorate.

4. The composition of claim 1, wherein said alkanolamine is used in aweight ratio of 1 to 2 parts per one part of the metal salt.

5. The composition of claim 1, wherein the aqueous solution has a pH inthe range of 7.4 to 8.0 when utilizing the copper complex and a pH inthe range of 9.5 to 10.5 when utilizing the cobalt complex.

6. A method of improving the stability of an aqueous algaecidecomposition containing an effective amount of a complex produced byreacting a water-soluble metal salt selected from the group consistingof copper salts and cobalt salts with an alkanolamine having at leastone alkanol group containing from 1 to 10 carbon atoms, said methodcomprising the step of incorporating with said algae-cide composition anacetylenic diol and an alkali metal halogenate, said acetylenic diolhaving the following structure:

' to l:l with respect to said complex.

where n is an integer of l or 2, said acetylenic diol 7. The method ofclaim 6, wherein the complex is being employed in a weight concentrationof 0.00] :l to S Wd n an aqueOuS S0l 1ti0n. 10:1 with respect to thecomplex and said halogenate The method of Claim 6, Where!" the Solutionhas a being employed in the weight concentration of 0.00l :1 PH of to

1. An algaecide composition having improved stability, consistingessentially of an aqueous solution containing an effective amount of acomplex produced by reacting a water soluble metal salt selected fromthe group of copper salts and cobalt salts with an alkanolamine havingat least one alkanol group containing from one to ten carbon atoms, saidsolution also having dissolved therein an acetylenic diol and an alkalimetal halogenate to provide increased stability for the complex andprevent decomposition of the same and precipitation of metal salts, saidacetylenic diol having the following structure: Ho CH2(-C * C-)n CH2OHwhere n is an integer of 1 or 2, said acetylenic diol being present in aweight concentration of 0.001:1 to 10:1 with respect to the complex, andsaid alkali metal halogenate being present in a weight concentration of0.001:1 to 10:1 with respect to the complex.
 2. The composition of claim1, wherein said acetylenic diol is 2-butyne-1,4 diol.
 3. The compositionof claim 1, wherein said alkali metal halogenate is sodium chlorate. 4.The composition of claim 1, wherein said alkanolamine is used in aweight ratio of 1 to 2 parts per one part of the metal salt.
 5. Thecomposition of claim 1, wherein the aqueous solution has a pH in therange of 7.4 to 8.0 when utilizing the copper complex and a pH in therange of 9.5 to 10.5 when utilizing the cobalt complex.
 6. A method ofimproving the stability of an aqueous algaecide composition containingan effective amount of a complex produced by reacting a water-solublemetal salt selected from the group consisting of copper salts and cobaltsalts with an alkanolamine having at least one alkanol group containingfrom 1 to 10 carbon atoms, said method comprising the step ofincorporating with said algae-cide composition an acetylenic diol and analkali metal halogenate, said acetylenic diol having the followingstructure: HO CH2 (-C * C-)n CH2OH where n is an integer of 1 or 2, saidacetylenic diol being employed in a weight concentration of 0.001:1 to10:1 with respect to the complex and said halogenate being employed inthe weight concentration of 0.001:1 to 10:1 with respect to saidcomplex.
 7. The method of claim 6, wherein the complex is dissolved inan aqueous solution.